The model discussed in this guide is horizontal force equivalent method (FHE) or also known as linear static, supported by the NSR -10. The procedure of this method is applied and described step by step for the study of a building with regular geometry I aporticado , of ten twelve y fifteen (10,12 and 15) stories in each of the seismic action by static lateral forces equivalent fundamental period is calculated is replaced , the design spectrum and base shear.